The invention relates to a water chamber that is made of plastic for a transverse-flow radiator for internal-combustion engines of a construction having a molded-on balancing chamber with a filler neck and filling lid containing pressure control valves, wherein a venting line connects a high point of the water chamber with a water inlet and a lower-disposed junction of the venting line connects into the balancing chamber and wherein there is a connection molded on in the bottom area of the balancing chamber for an ancillary-flow return line that is separate from a radiator return flow return line that leads to the suction side of a coolant pump.
In the case of a known chamber of this construction according to DE-A No. 33 30 710, the air venting line, when the junction into the balancing chamber is located at a lower point, requires a separate element, and its fastening requires additional manufacturing expenditures. The separate emptying of the water chamber and of the balancing chamber also requires considerable servicing expenditures for the separating of both line connections, or possibly additional construction expenditures for a discharge stopper.
In the case of a known radiator of a similar construction according to DE-A No. 33 41 390, the air venting line connects the balancing chamber with a high point of the radiator in the water chamber that is located opposite the junction of the forward flow line from the engine into the radiator. The balancing chamber, in its bottom area in the direction of the water chamber that is integral with it, has an open connection to its area from which the return flow line from the radiator to the engine leads out of the water tank. This development is not very suitable for a cooling circuit for liquid-cooled internal-combustion engines having a return-flow mixing thermostat because in that case, the ancillary venting flow remains inoperative until the cooling circuit opens, and the ancillary venting flow, by the inclusion of the radiator, prolongs the warm-up time of the engine. From DE-A No. 20 44 033, a radiator of a similar construction is also known in which an air venting line, from a high point of the radiator for a low-situated U-loop serving as a hydraulic lock is connected with a high point of the balancing chamber, and at the lowest point of the venting line, a connection is arranged to a joint discharge valve for the venting line, for the balancing chamber and via a connecting opening, to the chamber for the water chamber. This text contains no suggestions with respect to a development as plastic parts that meets the requirements of manufacturing.
It is the objective of the invention to further develop a water chamber made of plastic for a transverse-flow radiator of an internal combustion engine having a molded-on balancing chamber with a filler neck and filling lid containing pressure control valves, wherein a venting line connects a high point of the water chamber with a water inlet and a lower-disposed junction of the venting line connects into the balancing chamber and wherein there is a connection molded on in the bottom area of the balancing chamber for an ancillary-flow return line that is separate from a radiator return flow return line that leads to the suction side of a coolant pump. In such a system and with low manufacturing costs, the combination with a return-flow mixing thermostat is made possible without any functional disadvantages. In that case, the warm-up time must be short, the integral molding-out of the different radiator elements must be made easier, and a simple emptying of the cooling circuit must be possible. In order to achieve this objective, the invention provides for a water chamber made of plastic and having as a result, for a short warm-up period, the ancillary venting flow in the water tank, over a short path, leading from the forward flow line into the venting line; the venting line is molded directly onto the water chamber and the balancing chamber during their molding at low manufacturing expenditures; and the lower molded-out opening of the venting line houses a discharge valve that permits a simple simultaneous emptying of the radiator and the venting chamber as well as of the venting line itself.
An additional advantage occurs by the advantageous molding-out of the junction of the venting line into the balancing chamber at a parting plane between two portions of the balancing chamber is achieved so that special sealing measures for the molded-out openings are not necessary.
A further advantage arises in that a control line that connects to the venting line and leads to the pressure control valves in the filling lid is integrally molded onto the water or balancing chamber, without additional construction expenditures for separate parts. During the filling, while the mouth of the control line is open, the control line acts as an additional venting opening and, as a result, accelerates filling, when the junction of the venting line into the chamber has a throttled cross-section.
A still further advantage is obtained by an arrangement of the venting and/or control lines which are molded by webs onto either or both of the water and balancing chambers and which is particularly advantageous for plastic molding and avoids accumulations of material.
A still further advantage occurs when the web separates the water chamber and the balancing chamber.
A still further advantage occurs in molding-out of the venting and/or control lines as well as the integral molding of the filler neck onto the chamber and the development of the upper part of the balancing chamber being made transparent or translucent at least in the area of normal coolant level for the monitoring of the coolant level without impairing the development of the water chamber made of opaque material with high firmness and thus thin wall thickness and low weight. In this case, the independent possibility to construct the cross-section of the upper part of the balancing chamber to be approximately circular and thus secure with respect to deformation aids the use of a transparent or translucent plastic with low firmness, but still with a thin wall thickness and low weight.
The arrangement of the junction of the air venting line into the balancing chamber on both sides of a parting partition between an upper and lower portion thereof aids the molding-out of this junction by means of a mold slide that is arranged in a preform for the balancing chamber close to the parting plane and can be moved transversely to the molding-out direction.
Having the connection of the control line to the venting line in the lower part of the balancing chamber as well as laterally offset to the main part of the control line and with the control line in parallel to the venting line in the area of the upper part of the chamber aids in the molding process.
A further advantage resides in an arrangement of the balancing chamber with respect to the water chamber with a vent and control line connected to the water compartment by webs is compact with respect to space and has the venting and control lines extending between them in a protected way.
These and other objects, features, and advantages of the present invention will become more apparent from the following description when taken in connection with the accompanying drawings which show, for the purposes of illustration only, plural embodiments in accordance with the present invention, and wherein: